        (if (< n (-count string)) (.charAt string n)))
     ([string n not-found]
        (if (< n (-count string)) (.charAt string n)
-           not_found)))
+           not-found)))
 
   goog.global.Array
   (-nth

(defn- pr-seq [obj opts]
  (cond
    (nil? obj) (list "nil")
    (identical? undefined obj) (list "#<undefined>")
    :else (concat
            (when (and (get opts :meta)
                       (satisfies? IMeta obj)


(defn nil? [x]
  (identical? x nil))

(defn undefined? [x]
  (js* "(void 0 === ~{x})"))

(defn instance? [t o]
  (js* "(~{o} instanceof ~{t})"))
